Commit 365dad19 authored by Paul Eggert's avatar Paul Eggert

Use plain ‘static’ for Emacs C inline functions

This improved performance of ‘make compile-always’ by 8.2%
on my platform (AMD Phenom II X4 910e, Fedora 30 x86-64).
* src/conf_post.h (INLINE, EXTERN_INLINE, INLINE_HEADER_BEGIN)
(INLINE_HEADER_END) [!EMACS_EXTERN_INLINE]: Use plain ‘static’.
parent 507d5548
Pipeline #3057 failed with stage
in 53 minutes and 36 seconds
......@@ -373,8 +373,13 @@ extern int emacs_setenv_TZ (char const *);
#undef noinline
#endif
/* Use Gnulib's extern-inline module for extern inline functions.
An include file foo.h should prepend FOO_INLINE to function
/* INLINE marks functions defined in Emacs-internal C headers.
INLINE is implemented via C99-style 'extern inline' if Emacs is built
with -DEMACS_EXTERN_INLINE; otherwise it is implemented via 'static'.
EMACS_EXTERN_INLINE is no longer the default, as 'static' seems to
have better performance with GCC.
An include file foo.h should prepend INLINE to function
definitions, with the following overall pattern:
[#include any other .h files first.]
......@@ -399,20 +404,40 @@ extern int emacs_setenv_TZ (char const *);
For Emacs, this is done by having emacs.c first '#define INLINE
EXTERN_INLINE' and then include every .h file that uses INLINE.
The INLINE_HEADER_BEGIN and INLINE_HEADER_END suppress bogus
warnings in some GCC versions; see ../m4/extern-inline.m4.
The INLINE_HEADER_BEGIN and INLINE_HEADER_END macros suppress bogus
warnings in some GCC versions; see ../m4/extern-inline.m4. */
#ifdef EMACS_EXTERN_INLINE
/* Use Gnulib's extern-inline module for extern inline functions.
C99 compilers compile functions like 'incr' as C99-style extern
inline functions. Buggy GCC implementations do something similar with
GNU-specific keywords. Buggy non-GCC compilers use static
functions, which bloats the code but is good enough. */
#ifndef INLINE
# define INLINE _GL_INLINE
# ifndef INLINE
# define INLINE _GL_INLINE
# endif
# define EXTERN_INLINE _GL_EXTERN_INLINE
# define INLINE_HEADER_BEGIN _GL_INLINE_HEADER_BEGIN
# define INLINE_HEADER_END _GL_INLINE_HEADER_END
#else
/* Use 'static' instead of 'extern inline' because 'static' typically
has better performance for Emacs. Do not use the 'inline' keyword,
as modern compilers inline automatically. ATTRIBUTE_UNUSED
pacifies gcc -Wunused-function. */
# ifndef INLINE
# define INLINE EXTERN_INLINE
# endif
# define EXTERN_INLINE static ATTRIBUTE_UNUSED
# define INLINE_HEADER_BEGIN
# define INLINE_HEADER_END
#endif
#define EXTERN_INLINE _GL_EXTERN_INLINE
#define INLINE_HEADER_BEGIN _GL_INLINE_HEADER_BEGIN
#define INLINE_HEADER_END _GL_INLINE_HEADER_END
/* 'int x UNINIT;' is equivalent to 'int x;', except it cajoles GCC
into not warning incorrectly about use of an uninitialized variable. */
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment